<!DOCTYPE html>
<html lang="zh">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>两栏布局与三栏布局</title>
    <!-- 两栏布局 -->
    <!-- <style>
      .box {
        display: flex;
        margin: 50px auto;
        padding: 10px;
        background-color: aquamarine;
      }
      .left {
        width: 100px;
        height: 400px;
        background-color: yellowgreen;
      }
      .right {
        flex: 1;
        background-color: aqua;
      }
    </style> -->
    <!-- 三栏布局 -->
    <style>
      .box {
        display: flex;
        justify-content: space-between;
        margin: 50px auto;
        padding: 10px;
        background-color: aquamarine;
      }
      .left,
      .middle,
      .right {
        height: 400px;
      }

      .left {
        width: 200px;
        background-color: coral;
      }
      .right {
        width: 120px;
        background-color: lightblue;
      }
      .middle {
        flex: 1;
        margin: 0 20px;
        background-color: #555;
      }
    </style>
  </head>
  <body>
    <!-- 两栏布局 -->
    <!--  <div class="box">
      <div class="left"></div>
      <div class="right"></div>
    </div> -->
    <!-- 三栏布局 -->
    <div class="box">
      <div class="left"></div>
      <div class="middle"></div>
      <div class="right"></div>
    </div>
  </body>
</html>
